When the train approached also the sound of a Wartburg car approached and the appropriate Wartburg car of the Police and the uniformed guys. We finished taking the train pics with an unpleasant feeling. Besides another, for us unknown, railfan who was standing a little bit aside us three, none other than we could be the reason for the police operation. We were aware of the article which allowed taking pics at all public places excepted military areas and so on. As this was a very recent change of law we had made the experience that that not all railroaders already knew that and had prompted us to stop taking pics.
We were asked to hand out our passports and instructed to stop taking pics immediately. Without passport you had no chance to get back into the western part. After some minutes they started to ask questions: What we are doing? For what reason we are taking pics and whether we know something about the railfan who had been standing aside of us and who had been also taken to the police car by the policemen in the meantime? Where we are coming from? Etc. etc.
After getting this details we seemed to be very suspicious because it turned out that the other railfan came from the same place in Western Germany as we and the policemen didn't accept that we had said that we didn't knew each other.
After some time we got back our passports with the order to leave this area immediately.
This is a very subjective narration from our then situation. Today I think that we were treated formally correctly and that the policemen only had to follow the instructions they received.
The intimidation wasn't effective for a very long time. At Wuhlheide station we took pics of a freight train hauled by a class 52 engine on the bridge between Biesdorf and Grünau crossing.
Vopo is the abbreviation for Volkspolizist (member of the People's Police) in the former German Democratic Republic.